Patent Document 1 discloses a damping device having a floating structure. As shown in paragraph [0039] and [FIG. 2] in Patent Document 1, the damping device elastically supports an electronic device with respect to a case body in a non-contact state. The damping device includes damper members and shock absorbing member washers. The damper members and the shock absorbing member washers are made of an elastomer (e.g., a gel-like resin).
Patent Document 2 discloses a soundproof cover for exhaust gas recirculation (EGR) valves. As shown in paragraph [0030] and [FIG. 8] of Patent Document 2, the soundproof cover includes a sound insulation layer made of a urethane elastomer and a sound absorption layer made of polyurethane foam.